<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            margin: 0;
            padding: 0;
        }
        .box{
            width: 100px;
            height: 100px;
            background-color: red;
            /* position: absolute;
            left: 50%;
            top: 50%;
            transform: translate(-50%,-50%);
            transition: all 1s; */
        }
    </style>
</head>
<body>
    <div class="box">

    </div>
    <script>
        let box=   document.querySelector(".box")
           box.style.width="200px"
          console.log(box.offsetWidth);
           console.log(box.offsetHeight);
        



    </script>
</body>
</html>